If I'm going to sleep on something for the next 5-10 years it doesn't make sense to compromise and buy anything other than a new mattress if I don't have to. The hotel scenario is an exception, this is everyday. It's logical when you put it in context.
Lol. Many people buy "new to you" mattresses.
That’s an easily industrializable problem for mattresses. They’re standard size.
Seal them up in plastic when you’re done.
Getting them out of furniture or behind floorboards is harder.
That said, I would totally buy a second hand mattress. People buy used clothes all the time, isn't that similar? Could contain anything (including bed bugs, the top ddg hits seem to suggest).
If you buy used clothes you would (hopefully) wash and dry them thoroughly not just for bedbugs but for other parasites like head lice, chiggers, crab lice or whatever. Good luck cramming a mattress into the wash though :-P
For a person who normally can only afford a foam mattress one of the salvo's second hand inner spring mattresses is a 10 year investment that they will cherish.
See https://www.calrecycle.ca.gov/Mattresses/
Sometimes they're re-covered.
I bet you can move a lot of used mattresses if you dress them up like a fancy hotel room.